diff --git a/README.md b/README.md
index 32726f9..f3b56aa 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,8 @@ For class/module instance methods:
 require 'ruby2_keywords'
 
 module YourModule
-  ruby2_keywords def oldstyle_keywords(options = {})
+  ruby2_keywords def delegating_method(*args)
+    other_method(*args)
   end
 end
 ```
diff --git a/lib/ruby2_keywords.rb b/lib/ruby2_keywords.rb
index 7516af3..8c48333 100644
--- a/lib/ruby2_keywords.rb
+++ b/lib/ruby2_keywords.rb
@@ -1,7 +1,7 @@
 class Module
   unless respond_to?(:ruby2_keywords, true)
     private
-    def ruby2_keywords(*)
+    def ruby2_keywords(name, *)
       # nil
     end
   end
@@ -9,7 +9,15 @@ def ruby2_keywords(*)
 
 main = TOPLEVEL_BINDING.receiver
 unless main.respond_to?(:ruby2_keywords, true)
-  def main.ruby2_keywords(*)
+  def main.ruby2_keywords(name, *)
     # nil
   end
 end
+
+class Proc
+  unless method_defined?(:ruby2_keywords)
+    def ruby2_keywords
+      self
+    end
+  end
+end
diff --git a/ruby2_keywords.gemspec b/ruby2_keywords.gemspec
index 7ecacf4..623c58c 100644
--- a/ruby2_keywords.gemspec
+++ b/ruby2_keywords.gemspec
@@ -1,10 +1,10 @@
-version = "0.0.1"
+version = IO.popen(%W[git -C #{__dir__} describe --tags --match v[0-9]*], &:read)[/\Av?(\d+(?:\.\d+)*)/, 1]
 
 Gem::Specification.new do |s|
   s.name = "ruby2_keywords"
   s.version = version
   s.summary = "Shim library for Module#ruby2_keywords"
-  s.homepage = "https://www.ruby-rang.org/"
+  s.homepage = "https://github.com/ruby/ruby2_keywords"
   s.licenses = ["Ruby"]
   s.authors = ["Nobuyoshi Nakada"]
   s.require_paths = ["lib"]